Gaseous conduction device



Dec. 14, 1937. BARCLAY 2,102,191

GASEOUS CONDUCTION DEVICE Filed July 8. 1935 jfiuenibr jfobe'rtEBarclgy Patented Dec. 14, A a I Robert E. Barclay, Chicago, Ell, assignor to Fed= eral Electric Company, End, Chicago, m in corporation of New Josh Application July a", rest, Serial no. cases 35 Claims. (er. lid-1122) My invention relates in general to lamps and light lamp comprising closely associated sources has more particular reference to the provision of light componentswherein said sources com= of a lamp adapted to produce illumination sub prise various selected gaseous media adapted to antially identical to daylight. be excited by electrical discharge; a further ob An important object of the invention is to uti- 'ect being to employ mercury vapor, cadmiwn lize a plurality of light sources, each producing vapor, and neon gas as the sources of artificial a daylight component and all associated so that sunlight components.

the components may blend together and produce Another important object is to enclose each a resultant light that can be distinguishedirom of the gaseous media in envelope means defindaylight only by precise scientific measurement. ing a separate chamber or compartment for each 10 Another important object is to utilize electriof the media employed as a. component light cal discharge illumination for the purpose of source; a further object being to integrate the artificially producing approximate daylight. envelope means containing certain of the media Another important object resides in utilizing while another of the gaseous media is contained electrical discharge in a plurality of ionized gasein an envelope separate from the integrated en- 15 bus fields, including mercury, cadmium prefer-v velope; a still further' object being to integrate ably with a trace of gallium, and neon for the the envelopes containirigthe mercury and cadpurpose of producing approximate daylight. mium vapors to form a unitary lamp element I Another important object is to utilize crypton, while arranging the envelope, containing neon g0 argon or xenon-gas as a carrier for mercuryand gas, to encircle or embrace the unit containcadmium vapors in a'discharge device, crypton ing the mercury and cadmium vapors.

being preferably used as a mercury carrier and Mercury vapor, when excited, produces a char- Xenon as a carrier for cadmium. 'acteristic blue light, cadmium vapor produces Another important object is to provide alampv green, while neon gas emits a. reddish light, and

. having a plurality of discharge channels, each the invention contemplates the control of in of which channels contain a different gaseous tensity of these components by regulating the media, and having difierent cross-sectional areas cross-sectional area of the chambers containing. in order to obtain a desired intensity of illuminathe gases as well as the potential at which thetion in the various media in response to'electrigas-exciting discharge is accomplished. cal discharges, in said several media, at prede- Numerous other objects, advantages, and intermined potentials and currents and thus to herent functions of the invention will become approduce combined light having desired intensity parent from the following description, which,

of the several components. taken in connection with the accompanyin Another important object is to determine the drawing,- discloses preferred embodiments of the quality of artificially produced light by deterinvention. 35

mining the cross-sectional area of electrical dis- Referring to the drawing: charge paths in various gaseous conduction Figure l is a perspective view of a tubular elemedia employed to produce components of the ment providing a plurality of gaseous conduetiim Synthetic channels and adapted to be utilized in forming a 40 Another important object resides in produclamp embodying my present invention. 40

ing synthetic light, comprising several compo- Figure 2 is a sectional view taken substantially nents produced by electrical discharge in correalong the line 2-2 in Figure 1. sponding gaseous media, by enclosing several of. Figure 3 is a perspective view of a lei rip for formed in a sealed envelope, the separate chanmy present invention. 45 ncls being separated by a partitiong'preferably Figure 4 is a diagrammatic view of the lamp integral with the envelope, so that electrical dis and suitable electrical connections for operating. charge in one channel may be aided by heat the same. developed as a result of electrical discharge To illustrate my invention, I have shown on.

the gaseous media, each in a separate channel artificially producinggdaylight in accordance'with .50 in another of the channels in order thus to-imthe drawings. lamp ii for artificially producing prove the operating eificiency oi the device as daylight, said lamp comprising a plurality of sepwell asto'intimately associate the sources of the arate sources of light of character adapted to components of the resultant synthetic illuminacombine to form approximate daylight.

tion so produced. The lamp it comprises envelope means it and Anotherimportant object is to provide a day-= it forming a plurality of scaled channels is, it, 55

that gives the artificial daylight spectrum.

and ii, adapted each to contain a'suitable "gaseous media adaptedfor excitation by electrical discharge therein to artificially produce a sunlight component. To this end, the channel 83 contains mercury vapor. The channel l5 contains cadmium .vapor, preferably with gallium in sufficient quantity to provide, with the cadmium, a soft alloy when the ingredients solidify, as when the lamp'ds inactive forany lengthof time, and thus prevent cracking of the containing envelope. The channel ll contains neon gas. The envelopes also have suitable electrode means associated therewith for the purpose of exciting the gaseous media in the channels l3, l5, and ii, and cause the same to glow and emittheir corresponding sunlight components when electrical discharges take place through the excited gases functioning as conductors.

As is well known to those familiar with the phenomena of electrical discharge in gaseous conduction media, mercury vapor, when electrically excited by electrical discharge therein, produces a characteristic blue light; cadmium vapor produces a. green light, and neon a red light, and it is the combination of the spectra of mercury vapor, cadmium, gallium vapor, and neon gas By controlling the intensity of light produced by the excitation oithe gaseous media in the several channels it, it, and 81,1 am able to produce a synthetic light so closely approximating sunlight as to be substantially indistinguishable therefrom by normal human eyesight.

v The light intensity produced by electrical discharge in a. gaseous conduction medium varies as a function of current density of the discharge,

which, in turn, depends upon the cross-sectional area and length of the discharge path, the applied potential causing the discharge, the character of the gaseous conduction media, and, in making my sunlight lamp, I prefer to take advantage of the foregoing conditions in order to produce a neat and compact device and to overcome several dificulties which present themselves in designing a lamp for practical use.

I may, of course, employ separate envelopes for the several conduction media and mount the 4 several envelopes in close juxta-position, the gas in each envelope being energized at the potential required to produce a desired intensity of illumination in each gaseous medium. I prefer, however, for reasons which will hereinafter .be more fully explained, to form, as an integral cylindrical unit, the envelope means it defining the" elongated cadmium-gallimn vapor and mercur y-containing channels l5 and i3, the inteand difliculty may be encountered in initiating.

aioagci media, after which the heat of operation of the lamp will maintain these media in'properly vaporized condition. Crypton, xenon, or argon gases may be thus employed in the channels l3 and i5 in'conjunction with the mercury and cadmium-gallium alloy, since these-gases. when excited, do not emit much light and hence will have little, if any, eiiect; upon the resultant light emitted by the gases i3 and i5. I prefer, however, to use crypton gas, with mercury, since the same isqrelatively' inexpensive. Crypton gas gives a faint bluish-pink light when electrically excited. I preferto use xenon gas as a carrier for the cadmium or the cadmium-gallium alloy because of its low ionization potential and also because its atomic weight is close to that of cadmium. The'amount of cadmium and mercury in the channels l5 and 93 respectively is such as will keep the crypton gas insaturated condition when the lamp is in operation. I

Even where a carrier medium is thus utilized in the channels 53 and i5, it is ordinarily more dificult to initiate and maintain an electrical discharge in the channels l3 and I5, than it is in the channel ill containing the neon gas. I I consequently prefer to arrange the envelope l2,

vforming the channel ii, in such a way that said channel encircles and embraces the channels l3 and 85. This, as heretofore mentioned, may ccnveniently'be accomplished by forming the envelope 112 as a preierably-helically arranged tubular element, which may be assembled by mereiy sliding the same in place around the envelope means 58.

When the lamp is started in operation, the neon gas in the channel H is first excited by the initiationof electrical discharge therein and an electrostatic eflect is thereupon induced in the channels l3 and f5, which partially excites the gases in said channels and facilitates the initiation of electrical discharge in said channels whena suitable electrical potential is applied to the partial- 1y excited gases. In this way, the arrangement of the neon-containing envelope i2 is utilized to aid the operation of the mercury and cadmium lamp portions and, although the envelope, forml'ng the neon channel ll, may, if desired, be integrated with the envelopes forming the merf cury and cadmium channels it and i5, in which case the neon channel may extend parallel with respect'to the channels l3 and 55, I prefer to form the neon envelope as a separate element in order to facilitate the assembly thereof around the envelope means forming the channels 63 and 85; but I do not herein claim the broader aspects of invention relating to the use of an exciter for improving the operation of the gaseous conduction device, since the same forms the substance of my co-pending application, Serial No. 706,670,

filed January 15, 1934.

Iprefer also to make the discharge channel ll considerably longer and of lesser cross-sectional area than the channels l3 and I5 in order to obtain a desired relative amount of red light inthe channel IT with respect to the blue and green light produced in the channels 13 and I 5; and it is more convenient, therefore, to form the envelope l2 as a separate unit rather than integral with the envelope means defining the other channels l3 and I5.

I may also provide separate envelopes to define the channels l3 and I5 but prefer to employ integral ,envelope means It comprising a preferably cylindrical tubular envelope havinga partition l9 thereiiiwith the channels I3 and i5 sists in maintaining the cadmium in vaporized condition in thechannel l5 when the device is in operation. If separate envelopes are employed, it is necessary to operate the cadmium channel at a somewhat higher potential in order to generate additional heat to maintain the medium .in vaporized condition. By forming the element 18, as illustrated, I am able to considerably increase the operating eiiiciency of the device.

The envelope element may be. conveniently fabricated from cylindrical partitioned tubing of the character shown in- Figure 1, wherein the integral portion is offset on one side of the longitudinal axis of the tubing to provide channels of unlike cross-section within the cylindrical envelope and on opposite sides of the partition. Tubing of this, character may be conveniently fabricated in glass by the process taught in my Patent No. 1,904,348, issued April 18, 1933.

I prefer to operate the channels l3 and I5 in series, that is to say, with the same total current flow through each, and since it is necessary to maintain a somewhat higher temperature in the cadmium channel l5, than in the mercury chan- ,nel l3, the cross-sectional area of the channel l5 is made somewhat smaller than that of the channel l3, so that the current density will be higher and heat produced will be greater. The ratio of the cross-sectional area of the channels l3 and I5 is preferably approximately as 342 is to 75, since I find that this. ratio will afford a current density in the channel l5 suiiiciently high to maintain the cadmium in vaporized condition during the operation of the lamp. At the same time, the mercury vapor channel cannot satisfactorily be operated at a current density as great as that which has to be maintained in the cadmium channel I5.

The ratio of areaindicated above will furnish a suitable current density in each channel for maintaining the gases in proper condition for passing the operating discharge. Some of the heat, generated in the channel l5 by the relatively high current density prevailing therein,

will escape through the partition means I!) separating the channels and will assist in maintaining the mercury vapor channel at a temperature slightly higher than would otherwise be the case where'the channels l3 and i5 are formed in separate envelopes. The amount of heat thus escaping to the mercury vapor channel will aid in maintaining the mercury vaporized condition and thus avoid the danger-of impaired operation due to condensation of mercury vapor in the channel l3, which is likely to occur where the device is in operation under excessively low external temperature conditions. Moreover, the escape of heat from the channel l5 to' the chan-,

. nel l3 assists in conditioning the vapor in the cathode 21 by means of conductors at the other. These anode and cathode electrodes may be of any suitable construction and are mounted in suitable housings 25 sealed to and communicating with the channel l3 at the opposed ends thereof.

electrodes, including a cathode electrode 2| at one end of said channel and anode electrodes 23 For exciting the cadmium vapor in the channel .I5, I prefer-to employ a cathode electrode 21 and an anode electrode 29 at opposite ends of said channels, said electrodes 21 and 29 being of any suitable or preferredconstruction and mounted in suitablehousings3| formed at and communicating with the channel at opposite ends of the element l8. The cathode electrode 2| and the anode electrode 29 are preferably mounted at the same end of'the lamp element i8, while the anodes 23 and cathode 21 are mounted at the opposite end of the element in order to facilitate the electrical interconnection of the channels i3 and I5 in housing 31 disposed at the opposedends of the envelope and sealingly connected with the channel II. The electrodes 35 may be of any suitable or preferred character.

The neon gas, within the envelope I2, is ener- I gized from a suitable power source 39 through suitable conductors 4| interconnecting said power source with the electrodes 35. The cathode electrodes 2| and 21 also are or may be excited from suitable sources of cathode exciting power 43 and 45, the power source 43 being connected with the cathode 2| by means of the conductors 41, while the power source 45 is connected with the 49. I Discharge-creating potential is applied to the gases in the channels l3 and I5 from a suitable power source 5|, comprising, in the illustrated embodiment, the secondary winding of a transformer 53, the primary winding 55 of which is supplied with energy from a suitable power source through conductors 51, one of whichis connected at one end of the winding 55, the other being connected on said winding at its mid-point. The opposite ends of the winding 55 also are or may be electrostatically connected together through a condenser 59. V

The opposite ends of the secondary winding 5| are or may be connected by conductors 6| respectively with theanode electrodes 23, a condenser 63 being preferably interposed between the conductors 6|. The winding 5| is provided with a tap at its mid-point, which is connected, through a choke coil 65 and a control switch 61, to one of the conductors 49 leading to the cathode 21. The switch 61 remains normally open when the device is not in operation but is adapted to close automatically after a predetermined interval following the application of operating energy from the power sources 43 and 45 to the cathodes 2| ahd 21. To this end, the switch 61 has a shiftable element controlled from a power source $9, so that the switch closes after a predetermined interval following application of power from said source.

The power sources 39, 43, 45, and 69 may and preferably do comprise secondary windings of a 1 volt, applied by means of the winding 69, in

order to actuate the time-delay switch 61. A suitable voltage was applied to the winding 55 by means of the conductors to cause application of potential of the order of 100 to 200 volts alternately between the cathode 21 and each anode 23.

The vertical distance'between the cathode 21 and the anode 29 was substantially equal to the vertical distance between the cathode 2| and each of the anodes 23, this dimension being about 50 centimeters in the actual lamp heretofore mentioned. The tube I8 had an inner diameter of 41.5 millimeters, while the partition, which was 1.5 millimeters in thickness was offset approximately 12 millimeters from the longitudinal axis of the cylindrical envelope IS. The channel I! was 3.04 meters in length between the electrodes 35 and had an area of 28.2,? square millimeters.-

The gas pressures in the channels I3, l5, and I] were respectively V millimeter, millimeter, and 11 millimeters.

It will be seen that, upon closure of the switch 13, electrical discharge may immediately be ini tiated in the neon element l1 and that the cathode-exciting current may be appiled to the cathodes 21. The switch 61, however, may remain open so that the potential will not be applied upon the gases in the channels l3 and I5. After a short time delay, during which the cathodes 2| and 21 become excited to operating condition and the electrostatic effect is established in the channels l3 and I5 by the action of the neon element H, the switch 61 will close and a potential applied alternately between the cathode 21 and each of the anodes 23. This willcause discharge to take place alternately from each of the anodes 23 to the cathode 2i, and, since said cathode 2| is connected with the anode 29, a discharge will also take place through the gas in the channel II from the anode 29 to the cathode 21 contemporaneously with the discharges occurring through the gas in the channel It. In this fashion, the gases in the. channels l3 and I5 may be made to glow with their respective colorations and at a desired density. At the same time, since the neon lamp I1 is in operation, a red light will be emitted from this source, which, combining with the blue and green glows from the gases in the channels l3 and 15, will produce a compound light substantially identical to sunlight.

In operating the lamp, I find that the vapors of cadmium and gallium in the channel l5 tend to collect in any portion of the channel l5, which operates at a lower temperature than other portions ofthe channel. Corners and electrode pockets tend to operate at a lesser temperature than that prevailing in the channel intermediate the electrode pockets. In order to prevent the accumulation and condensation of cadmium vapor in the electrode pockets, I prefer to enclose the electrode pockets in a preferably cylindrical shell of any suitable metallic substance, the in-' wardly facing surface of which may be polishedv to form a mirror adapted to reflect inwardly and maintain a temperature within the electrode pockets suflicient toprevent condensation of the cadmium vapor at such places;

It is thought that the invention and numerous of its attendant advantages will be understood from the foregoing description and it is obvious that numerous changes may be made in the form, construction, and arrangement of the several parts of the illustrated apparatus without departing from the spirit or scope of my invention or sacrificing any of its attendant advantages, the forms herein described being merely for the purpose of illustrating'the invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Pat cut is as follows:

1. A gaseous conduction device comprising means forming a pair of adjacently extending elongated gaseous conduction elements, and an elongated embracing element arranged about,

said adjacently extending elements, wherein the adjacently extending elements contain gaseous conduction media of unlike character and adapted when excited to produce a synthetic light of predetermined color characteristics comprising the combined spectrum of the light produced by the gaseous media in the several elements.

2. A gaseous conduction device comprising means forming a pair of adjacently extending elongated gaseous conduction elements, and an elongated embracing element arranged about said adjacently extending elements, wherein the embracing element contains a gaseous conduction medium adapted when excitedlto produce light having 'diiferent spectrum characteristics from the spectrum characteristics of the light produced by the adjacently extending elements, whereby when all of the elements are excited the device will produce a synthetic light comprising the combination of the spectrums of all of the elements.

3. A gaseous conduction device comprising means forming a pair of ,adjacently extending elongated gaseous conduction elements, and an elongated embracing elemerit arranged about said adjacently extending elements, wherein the embracing element embodies a noble gas as a con.- duction medium, one of the adjacently extending elements embodying mercury and the other a noble gas with cadmium as conduction media. I

4. A gaseous conduction device comprising means forming a pair of adjacently extending, elongated gaseous conduction elements, and an elongated embracing element arranged about said adjacently extending elements, wherein the embracing element embodies a noble gas as a conduction medium, one of the adjacently extending elements embodying mercury and the other a noble gas with gallium as conduction media.

5. A gaseous conduction device comprising means forming a pair of adjacently extending elongated gaseous conduction elements, and an elongated embracing element arranged about said adjacently extending elements, wherein the embracing element embodies a noble gas as a con- 1 duction medium, one of the adjacently extending elements embodying mercury and the other a noble gas with an evaporable metal as conduction media.

6. A gaseous conduction device comprising a plurality of gaseous conduction elements, at least one of said elements comprising neon as a conduction medium and being arranged in helical coils embracing others of said elements, including an element embodying a noble gas with cadmium and gallium as a conduction medium and an element embodying mercury with a noble gas as a conduction medium.

7. A gaseous conduction devicecomprising a I plurality of gaseous conduction elements, at least one of which comprises neon gas as a'conduction medium and is arranged to embrace others ofsaid elements, including an element embodying mercuryand an element embodying anoble gas gated element comprising neon as a conduction medium arranged in position embracing the other elements.

9. A gaseous conduction device comprising gaseous conduction means forming a pair of elongated gaseous conduction elements respectively comprising mercury and cadmium as conduction media, and extending in adjacent relationship, and an elongated element comprising neon as a conduction medium'arranged in coils in position embracing the other elements.

10. A gaseous conduction device comprising envelope means defining a pair of channel portions, one of which contains mercury and the other cadmium as conduction media, and an envelope defining a channel containing gaseous neon as a conduction medium, said envelope being arranged to embrace the envelope means whereby, when electrical discharge isestablished in the gaseous contents of the envelope, the contents of the channel portions of the envelope means may become excited.

11. A gaseous conduction device comprising envelope means defining a pair of channel portions, one of which contains mercury and the other cadmium as conduction media, said envelope means comprising an integral partition separating the channels whereby the heat, generated by electrical discharge in the medium in one channel, may assist in establishing electrical discharge in the other. a

12. A gaseous conduction device comprising envelope means defining a plurality of chambers,- a conduction medium comprising mercury in one of said chambers, a conduction medium comprising cadmium in another oi said chambers, anda helix of neon embracing said chambers.

13. A gaseous conduction device comprising envelope means defining a plurality of chambers, a conduction medium comprising mercury and crypton gas in one of said chambers, a conduction medium comprising cadmium and xenon gas in another of said chambers, and a helix of neon embracing said chambers. s

14. A gaseous conduction device comprising integral envelope means defining a plurality of chambers, a conduction-medium comprising mercury in one of said chambers, a conduction me dium comprising cadmium in another of said chambers, and a separate envelope, comprising a tube, coiled about said envelope means and defining a channel containing neon gas.

15. A gaseous conduction device comprising means forming a pair of elongated gaseous conduction elements respectively comprising mercury and cadmium together with appreciable amounts of gallium as conduction media, said elements extending in adjacent relationship, and an elongated element comprising neon as a conduction medium, arranged in position embracing the other elements. r

16. A gaseous discharge device comprising envelope means having an integral partition decross-sectional area within the envelope means .flning a plurality of elongated chambers of unlike on opposite sides of the partition, and a gaseous conduction medium in each chamber and separated by' said partition.

1'7. A gaseous discharge device comprising envelope means dPfining a plurality of adjacent channel portions adapted to be electrically intercor'iected in series, in which the cross-sectional areas of'zsaid channel portions have the approximate ratio 455/100. 1

18. A gaseous conduction device comprising a sealed envelope having an integral internal partition defining a pair of elongated gaseous com duction channels within the envelope on opposite sides of the partition; and an elongated gaseous conduction element arranged about said adjacently extending channels.

19. A gaseous conduction device comprising a sealed envelope having an integral internal partition defining da pair of elongated gaseous conduction channels within the envelope on opposite sides of the partition and an elongated gaseous conduction element arranged about said adiacently extending channels, wherein said extending channels are of unlike cross sectional area.

20. A tubular element having an integral parti-' tion ofiset on one side of the axis of the element to define channels of unequal cross-sectional area of the element on opposite-sides of the partition, gaseous conduction media of unlike character in the said channels, and means to electrically interconnect the gaseous conduction media in series and to apply electrical potential across said series arrangement, whereby to obtain a desired current density in the'g aseous media in said channels.

21. A device as set forth in claim 20 including a gaseous conduction device encirclingand em bracing said tubular element whereby when energized to aid in the excitation of the media in said channels.

22. A gaseous conduction device comprising a plurality of gaseous conduction elements, at least one of which comprises neon as a conduction ele .ment and is arranged in helical coils embracing others of said elements, including an element embodying a noble gas with cadmium as a conduction medium and an element embodying mer embcdyng xenon with cadmium and an element embodying mercury as a conduction medium.

24. A gaseous conduction device comprising a plurality of gaseous conduction elements, at least one of which comprises neon as a conduction element and is arranged in helical coils embrac ing others of said elements, including an element embodying a noble gas with cadmium and a trace of gallium as a conduction medium and an element embodying mercury.

25. In combination, a discharge ing means forming taininga gas adapted to sustain electronic dis charge when excited, means to excite said gas comprising a sealed tubular member arranged about the discharge device in position to embrace device compristhe same, said tubular member containing gas-' a discharge channel concharge when excited','.'and means to excite said as comprising a sealed tubular member arranged in helical form around the discharge device and containing gaseous means adapted to carry high frequency electrical discharge oscillations, means to initiate high frequency oscillations in said tubular member in order to electrostatically energize the gas in said discharge channel, and electrode 'means cooperatively associated with said discharge device toexcite the gas in said channel.

27. A discharge device comprising. an envelope defining anelongated. channel containing a gaseous medium adapted to glow and emit light when electrically excited, means forming a second discharge channel containing a gaseous medium adapted to glow whenexcited and emit light is a color contrasting withWhe light emitted from the first mentioned channel, said second channel encircling said first channel, and means ,to create high frequency discharges in said second channel to cause the medium therein to glow and to subject the gaseous medium in the first channel to the electrostatic effect of the high frequency dis- Y comprising envelope means defining sealed chanin said tubular charges in said second channel whereby'to facilitatethe excitation of the medium in the first channel.

28. In combination, a pair of'coop'eratively associated discharge elements, said elements each nels containingwgaseous media adapted to glow -when electrically excited, andone element forming parallel adjacent channel portions, the other element having its channel embracing the channel portions of the firstelement whereby the operation-of the embracing element may electrostatically excite the gaseous media in said channelportions.

29. In combination,

sociated discharge elements, the first. adapted with said discharge channel and spaced from said' a pair of cooperatively asi for operation at relatively low voltage with relartively large consumption of power, and -the second one at least partially encircling the first one and adapted for operation atrelativelyhigh voltage with. relatively low power consumption, both of said elements. comprising envelope means defining sealed channels containing gaseous media adapted to glow when electrically excited, and the first .element forming parallel adjacent channel portions, said second element havingits channel helically disposed about the channel portions of the first element.' Z

30. In combination, a discharge device comprising means forming a discharge channel-containing a'gas adapted to sustain electronic discharge when excited, means to excite said gas comprising a sealed tubularmember arranged about the discharge device in position to embrace the same, said tubular member containing-gaseous means adapted to carry high frequency electrical oscillations,

means to generate oscillations member whereby to electrostat- 1 31. In combination, a discharge device comprising means forming a discharge channel containing'a gas adapted to sustain electronic discharge when excited, means to excite said gas comprising a sealed tubular member arranged about the discharge device'in position to embrace the same, said tubular member containing gas-. eous means adapted to carry high frequency elec-' trical oscillations, means to generate oscillationsin said tubular member whereby to electrostatically energize said gas, and electrode means cooperatively associated with said discharge device to apply discharge creating potential to said gas in said channel, said electrode means comprising a cathode at one end of said channel and a pluralityof spaced anodes operatively associated cathode.

32. In combination, electrical discharge means forming discharge channel portions containing gaseous media adapted to sustain electronic discharge when excited, a sealed tubular member arranged about said channel portions in position to embrace the same, said tubular member,

containing gaseous means adapted to glow when excited and emit light, said gaseous means being also adapted to carry high frequency electrical.

discharge-currents, means to utilize said currents in said tubular member whereby to electrostatically energize the gaseous media in said channel portions, and elect means cooperatively associated with said channel portions to apply discharge creating potential to the gaseous media therein, said gaseous media, when excited, being adapted to emit light of predetermined spectrum characteristics which, together with the ligl' t emitted by the gaseous means in the tubular member, provides a synthetic light of a desired spectrum.

33.A discharge device comprising an envelope defining channel portions containing. gaseous media adapted to be energized to" sustain electrical discharge therein, said channel portions being disposed -adjacentlywith dielectric means therebetween, spaced electrodes communicating with said adjacently disposed portions to. energize the gaseous media therein, and an exciter comprising a gaseous conduction device operatively associated with said adjacently disposed channel portions.

34'. A discharge device as set forth in claim 33, wherein the gaseous conduction exciter comprises a tubular element having portions disposed around and about said envelope, the conduction media in said channel portions and in the tubular exciter element being pre-selected to provide combined light of a desired spectrum whe excited.

35. 'I'he combination as set forth in' 'glaim' 28, whereinft he element which embraces the ad- }acent channel portions is arranged in helical orm.

ROBERT E.. BARCLAY. 

